OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at http://www.osha.gov.

August 25, 2011

Ms. Amie B. Falgout
128 Holden Drive
Lockport, LA 70374

Dear Ms. Falgout:

Thank you for your May 5, 2011, letter to the Occupational Safety and Health Administration (OSHA), Directorate of Enforcement Programs. You requested OSHA's interpretation of the difference in exposure limits for formaldehyde set by OSHA, as compared to those recommended by the National Institute for Occupational Safety and Health (NIOSH) and the other agencies listed in your letter. A member of my staff subsequently contacted you by phone. Your paraphrased scenario and questions are below, as expressed during the phone conversation. This response constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to other scenarios and questions.

Scenario: A set of air quality reports was obtained by your employer after testing three separate areas of a new modular building. The air quality tests were conducted in response to building occupants' complaints of symptoms consistent with formaldehyde exposure. The building air was tested for formaldehyde, acetaldehyde, acetone, and total volatile organic compounds (VOCs). The reports revealed that while the air quality measurements for formaldehyde were within OSHA's permissible exposure limit (PEL), they were above the recommended exposure limits of NIOSH and other agencies listed in the report of the air testing company.

Question 1: Why does OSHA's formaldehyde permissible exposure limit differ from the exposure limits of these other agencies?

Response: NIOSH is a research agency for occupational safety and health that publishes recommended exposure limits (RELs). The NIOSH RELs are not for enforcement purposes. OSHA's PELs are legal limits that are enforceable in workplaces covered under the Occupational Safety and Health Act of 1970. OSHA promulgated the PEL in its health standard for formaldehyde, 29 CFR 1910.1048, through a public rulemaking process that included a systematic review of occupational exposure data, epidemiology and animal studies, as well as considerations of engineering and work practice control measures that are economically and technologically feasible. The formaldehyde PEL was established in a final rule in 1992 (57 Fed. Reg. 22290, May 27, 1992) and has not been updated since then. At this time, a revision to the formaldehyde standard is not on OSHA's regulatory agenda.

You may be interested in a similar study of building air quality that was recently conducted by investigators at NIOSH and published this year on their public website. In this study*, NIOSH investigators collected samples for formaldehyde, VOCs, and other air contaminants, and they included a detailed discussion of the interpretation of the sample results. You may also be interested in a recent NIOSH report* published after an investigation of formaldehyde exposures to workers in a hair salon, wherein NIOSH provided a detailed discussion of their REL for formaldehyde and its proper interpretation on page 3 of the report. We have enclosed copies of these two NIOSH reports for your information.

Question 2: How should a worker decide to return to employment where known carcinogens exist at levels where the allowable limit is in question?

Response: The question as to whether you should return to work should be discussed with your employer and your physician. If you feel you are being exposed to serious safety or health hazards at your place of employment, you may file a complaint at www.osha.gov or you may contact the local OSHA office directly at:

Baton Rouge Area Office
9100 Bluebonnet Centre Blvd.
Suite 201
Baton Rouge, LA 70809
PH: (225) 298-5458 FAX: (225) 298-5457

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at www.osha.gov. If you have any further questions, please feel free to contact the Office of Health Enforcement at (202) 693-2190.

Sincerely,

Thomas Galassi, Director
Directorate of Enforcement Programs

Enclosures

cc: Ms. Dorinda J. Folse, Area Director of Baton Rouge Area Office